A new adjunctive tool to aid in the diagnosis of myogenous temporomandibular disorder pain originating from the masseter and temporalis muscles: Twin-block technique.

Myogenous temporomandibular disorder (TMD) is the most common type of nonodontogenic pain. The diagnosis is often elusive since diagnosing such conditions often requires a more comprehensive patient assessment. At present, there is no simple one-step diagnostic test to help render a definitive diagnosis of myogenous TMD pain. The twin-block injection can serve as a diagnostic aid to facilitate diagnosis of such myogenous TMD. The twin-block injection blocks the innervation to both the temporalis and masseter muscles, the two most common sources of referred pain to the teeth. This article reviews the twin-block technique along with a case report illustrating its potential role in the diagnosis and management of myogenous TMD pain of masseteric and temporalis origin.